Rotary drill bit



Aug. 25, 1959 5. w. PEASE, JR

ROTARY DRILL BIT Filed Oct. 4, 1957 INVENTOR. Gecaee VLFEASEA 2.

ATTORNEYS United States Patent ROTARY DRILL BIT George W. Pease, Jr., Fairfax, Okla.

Application October 4, 1957, Serial No. 688,335

6 Claims. (Cl. 255-61) This invention relates to an improved self-cleaning drill bit for use in drilling wells having both hard and soft formations.

The primary object of the invention is to provide a more efficient, reliable and desirable drill bit of this kind which has water courses arranged relative to its blades so that clogging of the blades during operation of the bit is eliminated.

Another object of the invention is to provide a drill bit of this kind which has radially extending and radially elongated and reinforced horizontal cutting blades, and central vertical boring blades, which are diamondinlaid on their cutting sides so as to substantially reduce wear thereon and to prolong the life and efficiency of the drill bit, the diamond inlays extending effectively to the cutting edges of the blades, and the trailing sides of the blades being reduced to eliminate non-functioning and unnecessary portions of the blades, so as to eliminate wear which would otherwise occur thereat, the blade being generally triangular in cross section.

A further object of the invention is to provide a drill bit of the character indicated above which can be made in well-finished, rugged, and serviceable forms at relatively low cost.

Other objects and advantageous features of the invention will be apparent from the following description and the accompanying drawings, wherein, for purposes of illustration only, a specific form of the invention is set forth in detail.

In the drawings:

Figure 1 is a perspective view of a drill bit of the invention;

Figure 2 is an enlarged bottom plan 'view of Figure 1;

Figure ,3 is a central vertical transverse section, taken on the line 3-3 of Figure 2; M

Figure 4 is a fragmentary horizontal section taken on the line 4-4 of Figure 3; and

Figure 5 is an enlarged vertical transverse section,

taken on the line 5-5 of Figure 4.

Referring in detail to the drawings, wherein likenumerals designate like parts throughout the several views,

the illustrated well drill bit comprises a relatively'flat .or

short conical body.10 comprising .a fiat circular disc portion 12 having in its peripheral edge closely and uniformly circumferentially spaced scallops or arcuate indentations 14 of equal length, which define therebetween unindented peripheral edge portions 16. On the upper side of the disc portion 12, and preferably integral therewith, is a reduced diameter central hub 18 of relatively small height, which is surmounted by a conical and externailly threaded tool joint 20. An axial water passage or chamber 22 extends through the disc portion 12, the hub 18, and the tool joint 20.

Radiating from the hub 18 and secured to the disc portion are equally circumferentially spaced, radially elongated reinforcing spokes 24, which have radially outwardly declining upper surfaces 26, and squared outer courses 38 which extend from the periphery of the boss. 32 into the axial water chamber 22, with some of the passages 36 and 38 being aligned or registered with each other, as shown in Figure 4.

Preferably formed integral with the underside 30 of the disc portion 12', and with and having brace portions 40 at and extending radially beyond the peripheral edge portions 16 of the disc portion 12, are radially elongated cutting blades 42, which radiate from the boss 32 and have substantially the same vertical dimension as the boss 32, as shown in Figure 3. As shown in Figures 1 and 5, the blades 42 are triangular in cross section and have angular reduced trailing sides 44 and right angular or perpendicular leading or working sides 46, and these sides intersect in relatively sharp lower or cutting edges 48 which are preferably flush with the underside of the boss 32. As shown in Figure 4, the trailing sides 44 are cut away at their radially inward ends, to define entrances 50 which open to related water passages or courses 36 and 38. The radially outward ends of the blades are sharpened by bevels 52, and are concentricallyrounded or concaved, .as indicated at 54 in Figure 2. Secured in any suitable manner to and covering the leading sides 46 of the blades 42 from the boss 32 to the outer ends 54 and from the underside 30 of the disc portion 12 to the lower edges 48 of the blades 42 are plates or inlays 56 of diamond-containing wear-resisting composition, which serve to virtually eliminate wear upon and distortion of the working sides 46 and of the lower edges 48 of the blades 42, when the drill bit is rotated in a direction to present the working sides 46 to material in a well in a drilling operation.

Because of the described forms of and cooperative arrangements of the horizontal and vertical water passages 36 and 38, respectively, accumulation and lodging of material between adjacent blades during operation of the drill bit is eliminated or reduced, so that clogging of the drill bit to an extent requiring pulling thereof from a well being drilled is eliminated.

Adequate rigidity and strength of the drill bit despite its relatively flat or vertically foreshortened form are obtaining by means of the bracing spokes 24 and the braces 40 extending over and along the portions of the blades 42 which reach beyond the peripheral edge of the disc portion 12.

Fixed on and preferably integral with and depending fromjthe underside 34 of the boss 32, are two substantially diametrically opposed boring blades 60, which are segmental or triangular in horizontal cross section, as shown in Figure 2. The outer sides 62 of the boring blades 60 are arcuate and coincide with the periphery of the boss 32. The flat trailing sides 64 of the blades 60 are in spaced parallel relation to each other; and the flat working sides 66 of the blades 60 are aligned with each other and with the working sides of two related blades 42, and have secured thereon extensions of the diamond-bearing plates 56 of these blades 42. The water passages 36 opening through the underside 34 of the boss at points near the Working sides of the boring blades 60, and open into related water entrances 50. The boring blades have flat horizontal lower ends 68.

' Although I have shown and described in detail herein a specific embodiment Olf the invention, it is to be understood that any changes in the forms of and in the relative arrangements of components can be made within the scope of the invention or defined ..by-.the.subjo-ined claims. i

What is claimed: 7 V

1. Ina well drill bit, a'flatldisc vportion having anunderside, a cylindrical axial .boss depending. frornsaid underside disc portion, circumferentially spaced horizontally elongated radialcutting bladeston the vunderside of said discportion and'radiating from said boss, said boss having an underside, and a pair of diametrically pposed segmental vertical boring blades on rand-depending from the underside of the boss,v-lthei-horizontal .cutting blades and the vertical boring blades having flat vertical working sides, the working sidesof some of the cutting blades being aligned withteach other across the bit and with working faces of the vertical boring blades.

2. In a Well drill bit, a flat disc portion havingan underside, a cylindrical axial boss depending from said underside disc portion, circumferentially spaced horizontally elongated radialcutting blades on the underside of said disc, portion and radiatingfrom said boss, said boss having an underside, and a;-pair of diametrically opposed segmental vertical boring blades ,on. and depending from the underside of the boss, the-horizontal cutting blades and. the vertical boring blades having fiat vertical Working sides, the Working sides OfSOlTiG' of the cutting blades being aligned with each other-across the bit and with Working faces of the vertical boringblades, the working faces ofthe cutting bladesxand :ofrthe boring'blades being covered .by diamond-bearing wear-resisting inlays.

3. In :a Well drill bit, a flat ,disc portionhaving an underside, a cylindrical axial boss dependingzfrom said underside disc portion, circumferentially spaced horizontally elongatedradial cutting blades onthe underside of said disc portion and radiating :from said boss,

pending from the underside of the boss, the horizontal cutting blades and the vertical boring blades: having flat vertical working sides, .the working sides ofisome of the cutting blades being aligned witheachiotherzacross the bit and with working faces of the verticaliboring. blades, a vertical axial water chamber"extendinguthrough said disc portion and into said boss and havingaiclosed lower" end -on a level 'below the'disc portion, and .water passages leading from saidchamber and traversing said boss below the disc' portion :and opening at the'sides of the boss between adjacent cutting blades.

4. A well drill bit comprising a flat circulardisc portion having a fiat underside anda peripheral edge, an upstanding axial hub on said disc portion, a zcylindrical axial bosson and depending from the underside of the disc portion, radial cutter blades on and depending from said underside and having inward ends-meeting said boss, said boss having an underside and said: cutting blades having lower edges on a level with the underside of the boss, a vertical water chamber formed in said hub, said disc portion and in said boss and having a closed lower end within the boss and on a level below the underside of the disc portion, radial water passages formed in said boss and leading from said water chamber to the exterior of the boss and opening into the spaces between adjacent cutting blades at the inward ends of the cutting blades.

5. A well drill bit comprising a flat circular disc portion having a flatgunderside anda -peripheral :edge, an upstanding axial hub on said disc portion, a cylindrical axial boss' on and dependingfrom the underside of the disc portion, radial cutter blades, on and depending from said underside and having inward ends meeting said boss, said boss' havi-ng an underside and said cutting blades having lower edges on a level with the underside of the boss, a vertical water chamber formed in said hub, said disc portion and in said boss and having a closed lower :end withinthe .boss :and on:,a level below the underside of the; disc-,portion,-radial water passages formed in said boss and leading from said water chamber to the ;.exterior of ,thezboss and opening into the spaces Ibetween adjacentcutting blades at the inward :endsof the cutting blades, :and .apair of vdiametrically opposed segmental boring bladesfixedon and depending from the underside of the boss and having lower ends spaced below thecutting blades.

-.-6. A well drillbit comprising aflat circularndisc portion having :a flatmndersideand ,a peripheraltedge, an

upstandingaxial :hub ,on said vdisc portion, a cylindrical axial .boss on :and depending fromutheunderside of the disc portion, radialcutter blades on and depending from said underside ;and havingtinward ends meet-ingsaid boss, said boss having an underside and said cutting blades'lhavinglower edges on a level :with the underside of the boss, a vertical water chamberformed in said :hub, said ,disczportion and in said'boss: and having a closed lower end-within the ,boss'and ona level below the underside of .the disc portion,; radial'water passages formed inssaidboss 7 .and-leadingrfrom: said water chamber to the zexte'rior of the =boss;. and openingrinto the spaces between adjacent cutting blades;;at-the inward ends ofuthe cuttingbladeaanda pair :ofgdiarnetrically opposed-segmental boringrblades fixed :on and depending from the punderside of the sboss :and. having lower 2 ends spacedxbelow; the cutting blades,; saidx boring blades having working ends and said cutting .blades having working sides, working sides of cuttingrblades being aligned rwithaand "parallel :to 'workingl'en'ds of .boring blades.

ReferencesCite'd-in the file of this patent UNITED STATES I PATENTS 

